含随机分布碳纳米管树脂基2D编织复合材料力学性能多尺度研究

发布时间：2018-04-21 13:31

本文选题：波形碳纳米管 + 随机分布　；参考：《电子科技大学》2017年硕士论文

【摘要】：2D编织复合材料因其良好的结构整体性、可设计性和抗冲击等性能,成为现代飞行器结构设计的重要选材之一。然而,研究表明:基体性能很大程度控制着2D纺织复合材料的关键力学性能。为提升和改善2D纺织复合材料力学性能,围绕树脂基体材料的改性和增韧研究,已成为提高2D编织复合材料综合力学性能的重要举措之一。目前,碳纳米管因其优异的力学特性,备受复合材料学术界和工业界高度关注,其可作为一种重要的增强体用于改性树脂基体性能。因此,研究含随机分布碳纳米管树脂基2D编织复合材料的力学性能及增韧机制,具有重要的学术价值和工程意义。本文基于均匀化等效思想和多尺度建模方法,研究了含随机分布碳纳米管树脂基2D编织复合材料弹性性能及影响因素。首先,在纳米尺度上,基于碳纳米管的实体纤维等效模型和改进的随机顺序吸附算法,建立了含随机分布波形碳纳米管增强树脂基复合材料的几何模型,基于连续介质力学方法,发展了基于特征胞元的含碳纳米管树脂基参数化有限元模型,并结合实验数据验证了所建模型的有效性。其次,基于2D编织复合材料编织工艺,建立了2D二轴1?1编织复合材料的实体单胞参数化模型,采用均匀化等效思想,嵌入含随机分布碳纳米管树脂基体材料等效本构,结合周期性边界条件,建立了基于细观胞元的2D编织复合材料弹性性能有限元分析模型,详尽分析了含碳纳米管改性树脂对2D编织复合材料弹性性能的影响,经与实验数据对比,证明了模型的合理有效性。研究发现:当树脂基体中碳米管直径为30纳米、体积分数为0.5%时,2D二轴1?1编织复合材料横向弹性性能提高了约10%~16%,其轴向弹性模量的增强效果与材料的编织角高度相关。最后,系统讨论了编织角和纤维体积含量对含碳纳米管2D二轴1?1编织复合材料的弹性性能的影响规律。
[Abstract]:2D braided composites have become one of the most important materials for the structural design of modern aircraft due to their good structural integrity, designability and impact resistance. However, the results show that the matrix properties largely control the key mechanical properties of 2D textile composites. In order to improve the mechanical properties of 2D textile composites, the modification and toughening of resin matrix materials have become one of the important measures to improve the comprehensive mechanical properties of 2D braided composites. At present, carbon nanotubes (CNTs) have attracted much attention in academia and industry for their excellent mechanical properties, which can be used as an important reinforcement to modify resin matrix properties. Therefore, it is of great academic value and engineering significance to study the mechanical properties and toughening mechanism of 2D braided composites containing randomly distributed carbon nanotubes resin matrix. Based on homogenization equivalence and multi-scale modeling method, the elastic properties and influencing factors of 2D braided composites with randomly distributed carbon nanotube resin matrix were studied in this paper. Firstly, based on the fiber equivalent model of carbon nanotubes and the modified random sequential adsorption algorithm, a geometric model of carbon nanotube reinforced resin matrix composites with random distribution was established. Based on the continuum mechanics method, the parameterized finite element model of carbon nanotube resin based on characteristic cell is developed, and the validity of the model is verified by the experimental data. Secondly, based on the braiding process of 2D braided composite, the solid unit cell parameterized model of 2D biaxial 1k-1 braided composite is established. The homogenization equivalent idea is adopted, and the equivalent constitutive model is embedded into the matrix material of carbon nanotube resin containing random distribution. Based on the periodic boundary conditions, a finite element model of elastic properties of 2D braided composites based on meso-cell was established, and the effect of modified resin containing carbon nanotubes on the elastic properties of 2D braided composites was analyzed in detail. Compared with the experimental data, the model is proved to be reasonable and effective. It is found that when the diameter of carbon rice tube is 30 nm and the volume fraction is 0.5 in the resin matrix, the transverse elastic properties of 2D biaxial 1 / 1 braided composites are improved by about 100.16%, and the axial elastic modulus enhancement effect is highly related to the braiding angle of the composites. Finally, the effects of braiding angle and fiber volume content on the elastic properties of 2D biaxial 1k-1 braided composites containing carbon nanotubes are systematically discussed.
【学位授予单位】：电子科技大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TB33;O341

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